Template Method Pattern in Python: Define Base Class with Algorithm Steps

from abc import ABC, abstractmethod


class DataProcessor(ABC):
    """Template method that defines the skeleton of an algorithm."""
    
    def process(self):
        """Template method - defines the sequence of steps."""
        self.load_data()
        self.clean_data()
        self.transform_data()
        self.save_data()
        print(f"Processing complete using {self.__class__.__name__}")
    
    def load_data(self):
        print("Loading data...")
    
    @abstractmethod
    def clean_data(self):
        pass
    
    @abstractmethod
    def transform_data(self):
        pass
    
    def save_data(self):
        print("Saving processed data...")


class CSVProcessor(DataProcessor):
    def clean_data(self):
        print("Cleaning CSV data - removing nulls and duplicates")
    
    def transform_data(self):
        print("Transforming CSV data - converting types")


class JSONProcessor(DataProcessor):
    def clean_data(self):
        print("Cleaning JSON data - validating keys")
    
    def transform_data(self):
        print("Transforming JSON data - flattening nested structures")


if __name__ == "__main__":
    csv_processor = CSVProcessor()
    csv_processor.process()
    
    print()
    
    json_processor = JSONProcessor()
    json_processor.process()